1. Field of the Invention
The present invention relates to a determination method of determining whether a shot image is a backlit portrait image and an image processing device having determination means.
2. Description of the Related Art
Taking a shot of foreground object such as person under a backlight condition against the sun or a light source typically results in an image having a background of larger luminance and the object or person of smaller luminance. In such a case, electric flash may be forced to increase the luminance of the object, so that details of the person such as facial expression can be taken with clarity according to the photographer's intention. However, the photographer does not always force the electric flash to emit.
In the case of taking a shot of object by a digital still camera (DSC), it is possible to perform image processing on the generated image data with relative ease. A variety of image processing techniques for image data have been proposed and are in practical use. Such image processing techniques include contrast correction, brightness correction, and color saturation correction based on given correction conditions selected by a user, and so-called automatic image quality adjustment such as contrast correction, brightness correction, and saturation correction based on the analysis results of the image data.
In the conventional image processing techniques, however, the analysis of image data characteristic may fail to properly determine whether the shot image is a portrait image under a backlight condition. In such a case, the user must determine proper photography conditions of the image data. That is, the automatic image processing by a personal computer may fail to successfully determine whether the image data is image data of backlit portrait image, and thereby preventing the automatic processing from being performed on the image data of backlit portrait image.